Post on 05-Jul-2020
DAM OVERVIEW AND TIMELINE
Outline
Topics covered in this presentation:
I. Description and timeline for Day–Ahead Market activities
II. Overview of System Implementation
III. Available Resources, Documentation, Sources
Market Participant Engagement
Slide 2
Presentation Objective
Using the information in this presentation…
…you will be able to understand
• Day-Ahead Market timeline
• Associated inputs/outputs
Slide 3
I. Description and Timeline for
Day–Ahead Activities
Day-Ahead Market
Slide 5
Day Ahead Market (DAM) provides
• Market for energy and Ancillary Services
• Platform to hedge congestion costs in the
day-ahead of the Operating Day
• Financial instruments to mitigate the risk of
price volatility in Real Time
Day-Ahead Market
Day-Ahead Market
Slide 6
Features of ERCOT’s DAM
• Co-optimization of Energy, Congestion
Revenue Rights, and Ancillary Services
• Financially binding
• Voluntary participation (except for Resources
under Reliability Must Run contracts)
Day-Ahead Market
Day-Ahead Market
Day-Ahead Timeline
Midnight 0600 1000 1330 1430
Day-Ahead
Execute
DAM
Execute
DRUC*
*DRUC: Day Ahead Reliability Unit Commitment
Slide 7
Day-Ahead Market
Information
By 6 am ERCOT publishes
• Ancillary Services (AS) Plan
• Load Ratio Shares (based on data from 14 days prior)
• AS Obligations
• Wind Forecasts and Production Potential – used to estimate
Current Operating Plan Resource limits for wind resources
• Operational Network Model *
• List of all Settlement Points *
• Mapping of Settlement Points to Electrical Buses *
• Competitive Constraints *
* new in nodal
Slide 8
Day-Ahead Market
Information
By 6 am ERCOT publishes forecasted system
conditions
• Load forecasts for ERCOT system, Weather Zones and
Load Zones
• Load forecast distribution factors to estimate load at the bus
level
• Distribution Loss Factors and forecasted ERCOT-wide
Transmission Loss Factors to account for energy losses
• Weather assumptions for forecasting system conditions
• Transmission constraints that have a high probability of
binding (new in nodal)*
Slide 9
Day-Ahead Market
Transactions
QSE submissions before 10 am in day-ahead
• Three-part Supply Offer
• Energy-Only Offers and Bids
• AS Offer
• AS Self-Arrangement
• Congestion Revenue Rights (CRR) Offer
• Point-to-Point Obligation Bid
• Capacity Trade
• Energy Trade
• AS Trade
• Current Operating Plan
Slide 10
Day-Ahead Market
Validating transactions
Phase 1 & 2
7 am in
day-ahead 10 am
Phase 1 only
Initial validation of the format
of submission, proper QSE
permission to make the
submission, offer caps, etc.
Credit exposure,
ownership, AS
Obligations, etc.
Note: Market system will cancel submission if it fails phase 2 validation
and send notice to the QSE containing reason for failure
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Day-Ahead Market
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Midnight 0600 1000 1430 1800
Day-Ahead
Execute
DAMExecute DRUC
Clearing Process
Calculate and Post
AS Obligation
Calculate and assign AS Plan quantity to each QSE based on Load Ratio Share.
Validate Inputs from QSEs
Validate inputs from QSEs including Offers, Bids, Trades, Schedules (Self-
Schedules and DC Tie Schedules), and Self-arranged AS.
Execute CRR Simultaneous Feasibility Test
Evaluate all CRRs using the Day-Ahead hourly Network Model.
Execute Ancillary Service Insufficiency
Check
Determine, prior to clearing the DAM, if there are sufficient AS offers to meet the
AS requirements.
Execute PTP Options Derating
Derate CRR Options declared for Real-Time settlement for the purpose for DAM
clearing.
Execute DAM Clearing Engine
Communicate DAM Results
Determine Energy, AS and CRR awards by optimizing the system-wide
economical benefits given bids and offers.
Post-process the outputs of DAM Clearing Engine and publish and communicate
the DAM results to Settlement and MIS.
Day-Ahead Market
Clearing Process
DAM simultaneously clears Energy Offers and Bids, AS Offers,
and CRR Offers/Point to Point (PTP) Obligation Bids.
DAM Clearing
Engine
Co-Optimization
Energy
Offers/Bids
AS Offers
Resource and
Network
Constraints
Energy
Awards
AS
AwardsCRR Offers/
PTP Bids
CRR/PTP
Awards
Slide 13
Day-Ahead Market
Mechanism of Clearing
DAM co-optimizes Energy, AS, and CRRs by maximizing bid-
based revenues minus offer-based costs given constrained
network security.
Maximize
The Gap
Bid-based Revenues
Offer-based Costs
Slide 14
Day-Ahead Market – Constraints
Constraints
modeled by
DAM
Power balance constraint
AS requirements
Transmission constraints
Resource capacity limits
Resource temporal constraints
Offer/bid quantity-block constraints
Offer/bid multi-hour block constraints
Slide 15
Day-Ahead Market – Output
Awards
• AS Offers
• Energy Offers
• DAM Energy-Only
Offers
• DAM Energy Bids
• CRR Offers
• PTP Obligation Bids
Output
Slide 16
Results published by 1:30 pm
Day-Ahead Market – Output
Prices• Day-Ahead Market
Clearing Price for
Ancillary Services (MCPC)
• Day-Ahead hourly
Settlement Point Prices
(SPPs)
• Day-Ahead hourly
Locational Marginal
Prices (LMPs)
• Shadow Prices
Summary info
• Quantity of total AS
Offers
• Aggregated AS Offer
Curve
• Total quantity of energy
(in MWh) bought in DAM
• Total quantity of energy
(in MWh) sold in the
DAM
Output
Slide 17
Results published by 1:30 pm
Post-DAM Activities
After DAM, QSEs have at least one hour (by 2:30 pm) to:
• Update Current Operating Plans to
reflect commitment of resources,
AS capacity awarded
• Submit additional Energy or Capacity
Trades to be considered in time for the
RUC process
Day-Ahead Market
Slide 18
2:30 Day-Ahead Market
Note that Three-
Part Supply
Offers are not
allowed during
this period.
Day-Ahead Market
=ERCOT AS Plan * QSE Load Ratio
ShareAS Obligation
in DAM
=QSE AS Obligation - Self-Arranged AS
submittedAS amount ERCOT
buys in DAM for QSE
=ERCOT AS Plan -SUM of Self-
Arranged AS
Submitted by QSEs
Total AS ERCOT buys
In DAM from AS Offers
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Applicable to QSE With Resources only
Day-Ahead Market
For each QSE and for each type of AS:
QSE AS Responsibility =Self-Arranged AS + AS sold in Trades -Total DAM AS
Offer awards
RUC Commitments
For AS+ Total SASM AS
Offer awards +
AS bought in
Trades
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+
50 50 50 50 5050 50 50 50 50
Hour
2 3 4 5 6
Day-Ahead Market – Trade Confirmation
Slide 21
Trade confirmation example
• QSE A submits a Capacity Trade for 50 MW for hours 2–6.
• QSE B confirms the trade by submitting matching trade of
50 MW for hours 2–6.
Day-Ahead Market – Trade Confirmation
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Trade confirmation example
• QSE A cancels hours 5–6.
Hour
2 3 4 5 6
50 50 50 50 5050 50 50 50 5050 50
Day-Ahead Market – Trade Confirmation
Slide 23
Trade confirmation example
• QSE A submits new trade for 100 MW for hours 5–6.
Hour
2 3 4 5 6
50 50 50 50 5050 50 50 50 50100 100
Trade confirmation example
• QSE B confirms 100 MW trade for hours 5–6 by submitting
a matching trade.
Hour
2 3 4 5 6
50 50 50 100 100100 100
Day-Ahead Market: – Trade Confirmation
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50 50
II. Overview of System Implementation
Implementation – Day-Ahead Desk
Slide 26
ERCOT Day-Ahead Operators:
• 2-person desk
• Staffed 5 am to 5 pm a day / 7 days a
week
– Enough time to review 6 am market postings and
information
– Can execute the Constraint Competitiveness Test (CCT)
and post results by 6 am
– Can execute a solved DRUC case to hand off to the
system operators for commitment/decommitment
Implementation – Training Overview
Slide 27
Training
• Nodal 101
• Basic Training Program
• Generation 101
• Generation 201
• Congestion Revenue Rights
Enroll using the Learning Management System at
https://www.ercottraining.com/lms/default.asp
Implementation – Testing Overview
Market Trials
• Integrated market trials with DAM start April 1 2010 (inputs
and outputs).
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Implementation – Testing Overview
Slide 29
Implementation – Testing Overview
Market Trials
Slide 30
*SASM: Supplemental Ancillary Service Market
March
DAM
2 x week
DAM/DRUC 5 x week
Add DRUC
2 x weekAdd HRUC,
SASM*
2010
April May
Market Trials
DAM testing will be scenario-based initially, with a phase-in
approach
• Guardrails on bids/offers
• QSEs with load will submit DAM Energy Bids for a
predetermined portion of their expected load
Implementation – Testing Overview
Slide 31
First week: run
DAM for energy
only and no
network
constraints
Second week:
energy and AS
together and no
network
constraints
Third week :
with constraints
Available Resources, Documentation, Sources
ResourcesDay-Ahead Market Trials Website for DAM Support information
Market Trials Handbook for Day Ahead Market
Explanation of Market Submission items – describes transactions, when they are
submitted, and how each submission affects previous submissions and inputs to the
market system
MMS Day Ahead Market Requirements
MMS Conceptual System Design
MMS White Papers – Special topics such as credit exposure study for DAM
System Implementation Guide whitepapers – Special topics such as combined
cycle and split generation modeling
General
Web Services interface specification
Market Manager User Interface design document
Market Manager User Interface user guide
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